Digestive Diseases Center, Showa University Koto Toyosu Hospital


What is Achalasia?

Achalasia is a rare disease that affects the nerves that supply the esophagus which results in loss of the normal contractions of the esophageal muscles.


  1. Dysphagia (Food gets stuck at the junction of the esophagus and the stomach)
  2. Regurgitation (A backward flowing of food)
  3. Chest pain
  4. Weight loss


  1. Endoscopy (Gastroscopy)
  2. High resolution manometry
  3. Barium Esophagram
  4. CT scan

These examinations can be performed in one-day hospital stay.
Please consult our GI physician if you have any of the above symptom.


Historically, achalasia has been treated by

  1. Laparoscopic Hellers myotomy
  2. Pneumatic dilation
  3. Botulinum injection (Botox)

Per-oral Endoscopic Myotomy (POEM) has been introduced by Professor Haruhiro Inoue in September 2008 and we have been performing over 2000 cases which is one of the largest high-volume center in the world. Clinical results at our center are excellent with no major complications with skillful doctors’ hands. POEM offers faster recovery after endoscopic esophageal myotomy with no incision, the ability to better tailor the procedure to the patient, and is potentially more effective in patients with advanced disease.

POEM for the treatment of achalasia

The POEM Procedure

  1. A gastroscopy will be performed to clean out residual food and determine the length of the required muscle incision.
  2. After injecting a saline solution under the mucosa, 1-2cm cut is given to mucosa = Mucosal incision
  3. Gastroscopy can be inserted in to the submucosal space and a submucosal tunnel is created to allow the scope to enter under the mucosa and gain access to the muscle = Submucosal tunneling
  4. After submucosal tunnel is created, the muscle incision (myotomy) is performed = Myotomy
  5. Once the myotomy is completed, the entry site is closed with clips = Mucosa closure

Detail of the procedure can be seen from the link below.

Frequently Asked Questions About POEM

What preparation is required before POEM?

Prior to the POEM procedure, patients will undergo a set of full examinations including a gastroscopy, an esophageal motility testing, barium esophagram (contrast examination), and CT scan. These can be done in one day hospital stay.

What will be planned 1 day prior to POEM
Patients will need to follow specific preparation instructions that include:

  • A liquid diet for one day prior to the procedure
  • No eating for 12 hours prior to the procedure

What is the recovery time and follow-up?

  • Following the procedure, we will perform gastroscopy and barium esophagram the next morning to confirm that there is no leakage at the surgical site. When that has been confirmed, the patient can begin drinking liquids.
  • One day after that (post operative day 2), the patient can return to soft foods.
  • The patient may experience mild pain which are mostly controllable with pain killers.
  • The patients may return to regular activity in about a week.

How safe is the procedure?

  • The first POEM procedure was performed in 2008 by Professor Haruhiro Inoue at our university. Since then, more than 2,000 patients were treated with POEM with satisfactory results.
  • All interventions have risks of adverse events but these risks are small.
  • There are reports of acid reflux after POEM, however most of our patients are satisfied with our results. There were only few patients with refractory acid reflux to medical therapy.

Why Showa University?

  • Showa University was the first institution in the world to perform POEM. Since then, we have been successfully treating patients from all around the world. We are confident that we would provide the best care available to treat achalasia or achalasia related disease.